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SVP
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Amphibian populations are declining in numbers worldwide. [#permalink]
 24 Oct 2007, 05:10
Question Stats:
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 0% (00:00) wrong based on 0 sessions
Amphibian populations are declining in numbers
worldwide. Not coincidentally, the earth’s ozone
layer has been continuously depleted throughout the
last 50 years. Atmospheric ozone blocks UV-B, a
type of ultraviolet radiation that is continuously
produced by the sun, and which can damage genes.
Because amphibians lack hair, hide, or feathers to
shield them, they are particularly vulnerable to UV-B
radiation. In addition, their gelatinous eggs lack the
protection of leathery or hard shells. Thus, the
primary cause of the declining amphibian population
is the depletion of the ozone layer.
Each of the following, if true, would strengthen the
argument EXCEPT:
(A) Of the various types of radiation blocked by
atmospheric ozone, UV-B is the only type
that can damage genes.
(B) Amphibian populations are declining far more
rapidly than are the populations of
nonamphibian species whose tissues and
eggs have more natural protection from
UV-B.
(C) Atmospheric ozone has been significantly
depleted above all the areas of the world in
which amphibian populations are declining.
(D) The natural habitat of amphibians has not
become smaller over the past century.
(E) Amphibian populations have declined
continuously for the last 50 years.
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Intern
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Re: CR: Amphibian Population [#permalink]
24 Oct 2007, 05:52
pmenon wrote: Amphibian populations are declining in numbers
worldwide. Not coincidentally, the earth’s ozone
layer has been continuously depleted throughout the
last 50 years. Atmospheric ozone blocks UV-B, a
type of ultraviolet radiation that is continuously
produced by the sun, and which can damage genes.
Because amphibians lack hair, hide, or feathers to
shield them, they are particularly vulnerable to UV-B
radiation. In addition, their gelatinous eggs lack the
protection of leathery or hard shells. Thus, the
primary cause of the declining amphibian population
is the depletion of the ozone layer.
Each of the following, if true, would strengthen the
argument EXCEPT:
(A) Of the various types of radiation blocked by
atmospheric ozone, UV-B is the only type
that can damage genes.
(B) Amphibian populations are declining far more
rapidly than are the populations of
nonamphibian species whose tissues and
eggs have more natural protection from
UV-B.
(C) Atmospheric ozone has been significantly
depleted above all the areas of the world in
which amphibian populations are declining.
(D) The natural habitat of amphibians has not
become smaller over the past century.
(E) Amphibian populations have declined
continuously for the last 50 years.
Ans. is A => UV-B is a radiation and is blocked thus doesnt harm the amphibian populations
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Manager
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I think its D,whats the OA?
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Intern
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I'm kinda torn between D and E.
E does not strenghen or weaken, just repeats the stem
Although, I'd pick D. Stem suggests that through the past 50 years "the primary cause of the declining amphibian population is the depletion of the ozone layer" , but D says that "The natural habitat of amphibians has not become smaller over the past century." So everything's fine 
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Intern
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linau wrote: I'm kinda torn between D and E. E does not strenghen or weaken, just repeats the stem Although, I'd pick D. Stem suggests that through the past 50 years "the primary cause of the declining amphibian population is the depletion of the ozone layer" , but D says that "The natural habitat of amphibians has not become smaller over the past century." So everything's fine I was hesitating to pick D but finally what I understood is that since the natural habitat has not become smaller it means that it's not caused by men or some other predator that can have a geographically localized action.
In other terms only a radiation over all the natural habitat of the amphibian will kill them without reducing the surface of their natural habitat.
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Senior Manager
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Re: CR: Amphibian Population [#permalink]
25 Oct 2007, 22:05
Another D.
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Re: CR: Amphibian Population
[#permalink]
25 Oct 2007, 22:05
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